This invention relates to a gear train arrangement, particularly a worm gear arrangement having a worm wheel elastically mounted on a catch plate driving in turn an output shaft which can be used among other things to provide a lift drive mechanism for automobile windows.
In a known worm gear arrangement utilized in a motor vehicle window-lifter drive, a separate, metallic catch plate is fit-mounted and fastened. It is mounted on the end of the steel output shaft facing away from the output side, which is mounted in the gear housing using standard sintered sleeve bearings. Concentric to the output shaft around the circumference of the catch plate are projecting pins attached in an axially free-standing fashion which mesh - when the gear train is assembled - with corresponding pockets distributed around the circumference of the worm wheel. To avoid gear damage, for example, when the catch plate reaches a stop when attaining the upper or lower end position due to the action of the motorized window-lifter drive, damping buffers of elastic material are slipped over the pins; to permit the required relative motion between the catch plate on the one hand and the worm wheel on the other, the worm wheel is mounted in a rotating fashion on the output shaft, specifically axially between the sintered bearings for the actual sleeve bearing of the drive shaft in the gear housing.
It is the object of this invention to develop a design assuring higher operating reliability for the gear train, particularly considering the extensive operating temperature ranges when utilized as part of a motor vehicle window-lifter drive. It is a further object of this invention to provide a design permitting less overall height in the direction of the output shaft and simpler manufacture and assembly engineering.